//app.js
App({
    onLaunch: function () {
        var that = this
        //获取屏幕尺寸，放到全局结构中
        wx.getSystemInfo({
            success: function (res) {
                that.globalData.scHeight = res.windowHeight
                that.globalData.scWidth = res.windowWidth
            },
        })
    },
    globalData: {
        userInfo: null,
        scWidth: 0,             //全局的屏幕尺寸，已经去掉了上边的标题栏
        scHeight: 0
    }
})